Four 2015 Energy Ideas 'Back to the Future' Got (Almost) Right

Hoverboards, flying cars, and auto-fueling are closer than you think, and garbage energy is here.

Energy is so cheap and easy in 2015 that we all have flying cars and robot gas attendants. That's not the reality as of New Year's Day, of course, but rather the "future" depicted in the hit 1989 movie Back to the Future Part II.

Director Robert Zemeckis never intended to paint a realistic forecast, but it's amazing how much of his vision of energy is taking shape. Science is trying to deliver not only skyward transport and renewable fuel, but also efficiency and solutions to lower greenhouse gases. Some examples:

1. Hoverboards

Don't believe all you see on the Internet about the hoverboard, the airborne skateboard Michael J. Fox's Marty McFly commandeered in the movie. Early this year, former pro skateboarder Tony Hawk demonstrated one with aerial acrobatics in a star-studded viral video that was a hoax. Hawk and actor Christopher Lloyd, who played lovable, wild-eyed inventor Doc Brown in the Back to the Future movies, revealed it was all a gag orchestrated by Funny or Die. (Related: "If We Only Had Wings.")

But Arx Pax, a company in Los Gatos, California, says it has developed a real magnetism-driven hoverboard. It will be presented to the first ten $10,000 investors in the company's successful Kickstarter campaign, right on schedule: a launch event on October 21, 2015, the date Marty and Doc landed in the fictional future. A New York Times reporter test-drove the firm's Hendo Hoverboard this fall, and Time magazine named it one of the 25 best inventions of the year.

Inventor Greg Henderson said the true innovation is not the attention-grabbing hoverboard, but his patented Magnetic Field Architecture technology, which he says has disruptive potential to slash energy consumption and boost disaster resilience. The new approach to magnetism, he said, "is the easiest, most efficient way to separate an object from the Earth and to overcome friction."

Previous incarnations of magnetic levitation, or mag-lev, have been problematic and expensive. The mag-lev line Japan aims to build by 2027 costs more than $500 million a mile (1.6 kilometers), much of that expense because the train won't levitate until it reaches a threshold takeoff speed. (Related: "Pictures: Amazing Transportation Inventions.")

But Henderson said that the first-generation iteration of his technology can lift an object using as little energy as 40 watts per kilogram (2.2 pounds). He said some helicopters can burn four times as much energy getting off the ground.

Granted, Arx Pax's technology needs nonferrous metal surfaces to work; the Hendo Hoverboard has been tested (including by former pro Hawk) over a copper half-pipe in the lab. Technology already exists for road surfaces with the needed properties: Researchers have developed conductive concrete for keeping bridges ice-free in snowstorms and eliminating the need to shovel sidewalks and driveways. If conductive road material were embedded in soil for vehicles that don't touch ground, thoroughfares could be planted with carbon dioxide-storing vegetation.

"Why not plant the HOV lanes with low-level ground cover, so they become, instead of freeways, greenways?" asked Henderson.

The potential to air-cushion buildings and other structures against earthquakes, or the effects of sea-level rise, may be even greater than the promise of transport applications, said Henderson, who is an architect. (Related: "Sustainable Cities: Challenges and Opportunities in Japan.")

The inspiration for Arx Pax's technology came in 1989—not that year's Back to the Future sequel, but northern California's Loma Prieta earthquake. Embedding it first in a hoverboard helped ignite imaginations, says Henderson’s wife and firm co-founder, Jill.

"We are so grateful that it has had this response, this magical device that was actually able to happen and can be a springboard to all these meaningful technologies that are truly passions of Greg's and mine," she said.

2. Flying Cars

"Roads? Where we're going, we don't need roads," says Doc Brown in Back to the Future's seminal kicker line.

Jack Langelaan, associate professor of aerospace engineering at Pennsylvania State University, says it's not surprising that the flying car technology has been slow to arrive, since engineering requirements for road and air travel are utterly different. "The big danger is that because the 'flying car' is a hybrid, you could end up making something that's both a bad car and a bad airplane," he says.

Langelaan was part of a team that won a 2011 challenge, sponsored by Google and hosted by NASA, by designing an electric-powered four-seat aircraft and flying it 200 miles (322 kilometers) at 107 miles (172 kilometers) per hour, with an average fuel efficiency of 403 passenger miles (648.5 kilometers) per gallon. (Related: "How Much Does Traffic Cost?")

Engineers working on the problem have taken vastly different approaches, he says. Some have sought to build something more like an airplane, only operable by a trained pilot. Others have aimed to create vehicles closer to those in Zemeckis's futurescape: so automated any driver could maneuver them. (Related: "Will Driverless Cars Decrease Fuel Consumption?")

Langelaan believes Google's nascent technology for driverless cars will help jump-start those efforts. Collision avoidance know-how will have to be built into self-driving and sky-cruising automobiles alike, he says. (Related: "Energy Implications of Autonomous Vehicles.")

But Dietrich expects it will be a decade until Terrafugia achieves high automation; it will take skilled pilots to drive the prototypes his company hopes to deliver by 2017. (Related: "Flying Car Makers Tout Test Flights.")

"In my opinion, it's the ultimate incarnation of personal freedom," said Dietrich. "That's what made the car so popular. The flying car is the next level. I think we'll continue to dream about it until we have it."

3. Automated Fueling

While cars stay earthbound for the foreseeable future, one of the advances that wowed Marty McFly may actually arrive by 2015.

A robotic fueling system introduced by Husky, a leading maker of fuel nozzles and accessories, is to be rolled out in the U.S. Midwest within the year. The fuel pump doesn't talk or wheel around your car, checking systems, like the one in the movie's flying car service station. But a compact flexible nozzle extends to open a car's gas tank and offer a hands-free fill-up.

Husky, a 66-year-old Pacific, Missouri, company, teamed up with Stockholm-based start-up firm Fuelmatics Systems to create the product, unveiled at last year's National Association of Convenience Stores trade show.

Robotic fueling is, indeed, all about convenience, said Sten Corfitsen, founder and chief executive of Fuelmatics, in a demo video that Husky has posted on Youtube. "It's cleaner. You don't have to take the dirty nozzle," he said. "It's more safe at nighttime. Maybe you don't like to step out of the car."

View Images

A Dutch company developed TankPitstop, an automated fuel fill-up robot (above). A robotic system for hands-free fill-ups, introduced by Husky, is to be rolled out in the U.S. Midwest in 2015.

Photograph by Michel Porro, Getty Images

Fuelmatics said customers will be able to operate the system via a phone app. All the unit will need is a start signal; it will have a vacuum-based automatic shutoff. Fuelmatics's website said its system can dispense gasoline, diesel, "and a new fuel like ethanol or natural gas" from the same unit. (Related: "For Natural Gas-Fueled Cars, Long Road Looms Ahead.")

But technology to turn garbage into methane fuel has been commercially available for 30 years, said Kristi Moriarty, a senior analyst at the U.S. Department of Energy's National Renewable Energy Laboratory. It's called anaerobic digestion, or the use of microorganisms to break down organic material in the absence of oxygen. (Related: "Methane—Good Gas, Bad Gas.")

Moriarty said the city-garbage-to-city-fuel loop makes sense because it brings efficiency to the biogas process, but it is still relatively expensive and not widely used. For one thing, regular household garbage contains material that isn't biodegradable and has to be separated, such as batteries. Second, the energy "density" of waste-produced biogas, at only 60 to 70 percent methane, is less than that of natural gas produced by the fossil fuel industry, at more than 95 percent methane. That means biogas packs less punch for heating or for powering vehicles.

In the United States, fracking has helped make the cost of natural gas so low that biogas now has a hard time competing. "It's not that you can't do it, technologically," said Moriarty. "It's that it doesn't financially make sense. People won't do it." (Related: "Urban Ski Slope to Raise Profile of Europe's Waste-to-Energy Drive.")

Last year, Moriarty's analysis showed a proposed regional food waste digester for an old industrial landfill site near New Orleans wouldn't make enough revenue to cover costs, because it would have to compete with Louisiana's landfill use prices and cheap fossil fuel.

But in many parts of the developing world, garbage-to-energy makes economic sense today. For example, Moriarty and colleagues found a planned project to turn palm-oil processing waste into biogas in Muaro Jambi, Indonesia, would garner a huge return on investment.

The fuel would be sorely needed by villagers, who were relying on expensive, dirty petroleum diesel generators for power. For such energy-poor communities with degradable waste at hand, biogas "really is a win-win," said Moriarty.

That's a sermon long preached by National Geographic Emerging Explorer T. H. Culhane. After installing many biogas systems in the developing world, he and his nonprofit, Solar CITIES, are now working on small home biogas systems for farm families, environmentalists, and households seeking more reliable off-grid energy. They trade ideas at his organization's active online community; for example, Culhane said the fertilizer they produce as a biogas by-product is so valuable that it helps offset costs. (Related: "On Mount Everest, Seeking Biogas Energy in a Mountain of Waste.")